Hello Prasimix,
at first, I'm very impressed of all your efforts you put in that project and can't wait to see the finished psu.
I'm also planning a dual power supply with similar features you have at 0-30 volts and 0-10A.
I'm often test circuits with vacuum tubes so i need a little bit more current
.
My plan and I hope it will work is to use directly a switching supply from Cosel. It is a pba 300 with 36 volts and current of 9 ampere but it could handle 10 ampere
.
This I will also pre regulate via a circuit so that the pre voltage which is feed into the post regulator is 4-5 volts higher than the output.
We will see, if that is working. Advantage of that is, that I not to have a big transformer with bridge rectifier etc. so that will save money and place in the enclosure.
I saw in one of the post, that you are still search for how to save io's on the arduino.
And would give you the hint maybe to use a different display.
My plan is to use two 4" inch displays with touchscreen from nextion. These displays are controlled via a serial interface. The screen pictures keyboards etc. are all made with an editor. Also a scope function is existing, cause I will use that to show the traces current, voltage and power at a time line like a scope on that display. Maybe it is interesting for you too.
Here is the link :http://wiki.iteadstudio.com/Nextion_HMI_Solution
Hopefully we will hear from you soon, with some progress on that project
Cheers
Sven